As one type of hybrid vehicles, there is a drive device for a hybrid vehicle provided with a clutch on a power transmission path between an engine and a MG. This hybrid vehicle can selectively use at least one of the engine and the MG as its operational drive source. Generally speaking, a MG operation which disengages the engine by releasing the clutch mechanism and exclusively uses the MG as the drive source is selected during a low vehicle speed and low load operation of the vehicle, and an engine operation which at least uses the engine as the drive source by engaging the clutch mechanism is selected during a high load operation and high vehicle speed of the vehicle. This kind of hybrid vehicle is described, for example, in Patent Document 1.
With this kind of hybrid vehicle, when an engine starting condition is satisfied; for instance, upon transition from the MG operation to the engine operation, when a power generation request for storing electric energy in a power storage device is sent, or when a warm-up request for warming up the engine is sent, the engine is started, the rotation speed of the engine is increased, and the clutch mechanism is engaged after the engine has been started to accelerate the vehicle.    Patent Document 1: Japanese Patent Application Publication No. 2004-204963